Control mechanism for presses



Sept. 5, 1939.

CONTROL MECHANISM FOR PRESSES Filed Sept. 11, 1957 & E/% O o 33 22 l I), /7 22 "g 7 I? m. m j if 2/ FlG.-| 37 A70. /9a 27 O .2 11" :D o c I J /L /4 /d' 5 20.120 206 7 li 2; 2 M /J' I INVENTOR ELBERT L. HYDE B Mz%% 4 ATTORNEYS E. 1.. HYDE 2,171,565

Patented Sept. 5, 1939 iiNl'lED STATES PATENT OFFIfiE CONTROL MECHANISM FOR PRESSES Ohio Application September 11,1937, Serial No. 163,421

3 Claims.

This invention relates to'improvements in control mechanism for pressing machines.

An object of the invention is to provide in a power closed pressing machine control means for the power means operable by a pair of spaced safety manuals having two stages of operation. In such a control mechanism I provide the novel step of connecting the manuals with a stay-put valve for controlling the power means in such a manner that during the first stage of manual operation the manuals and associated mechanism are connected with the control valve and so constructed and arranged as to return to unoperated position if the manuals are released. Means is provided, however, for enabling second stage of operation of the manuals if the press is safely closed, at which time the manual means is disconnected from the control valve means, which, upon release of the manuals, will stay in its actuated position and hold the press closed.

Other novel features of my invention will be apparent from the accompanying specification and drawing and the essential features will be set forth in the claims.

In the drawing Fig. 1 shows an end elevation of a pressing machine with the control mechanism therefor shown diagrammatically; Fig. 2 is a view similar to Fig. 1 showing in full lines the press parts in safe closed position and in dotdash lines the same parts in fully closed position. This view shows diagrammatically the position of the control mechanism just prior to the parts reaching safe closed position; Figs. '3 and 4 are views of the control mechanism of Figs. 1 and 2 in the position corresponding to a fully closed pressing machine before and after the manuals are released; Fig. 5 is an enlarged detail view of a portion of the mechanism of Figs. 1 to 3; while 6 is an enlarged detail view showing an elevation taken from the right side of Fig. 5.

In the drawing I have illustrated a pressing machine having a frame H1 supporting a bed II and a yoke E2 which carries a head l3 in and out of engagement with the bed I I upon actuation of toggles M by the fluid motor IS. A spring it; returns the head toward open position. Motive fluid is supplied to motor 15 from supply conduit ll through rotary valve l8 and conduit 19. Valve i8 has a casing provided with an exhaust port 550. and air supply ports [8b and I8c. Within the casing is a valve core member ltd operable by the handle 86. The core has a passage 18 The valve handle has a pin and slot connection with the arm 29a of lever 25 and the other arm 2% has a pin and slot connection with a suitable mechanism operable by a two hand control to move valve core l8d.

In the form shown, the connection between the valve actuating bellcrank 2D and the safety manuals comprises a two part link Z l. The lower end of this link 2 la has a pin and slot connection with the arm 20b of the bellcrank. At its upper end it carries a pair of latch members 22 pivotally mounted on the link and spring pressed outwardly by spring 23. Stop portions 24 on the link limit the outward movement of the latch members. The upper end of the link 2 lb carries a pair of arms 25 having slotted openings 26 in which the latches 22 engage. On a fixed portion of the frame I provide a pair of spaced members 21 for disengaging the latches, as will later appear. The portion Zlb of the link 2| is carried centrally of a whiflfletree 28 which is connected at its ends by links 29 with manuals 38 and 3| respectively. These manuals are returned to their uppermost position by springs 32. First stage operation of the manuals occurs until they strike the blocks 33, which are in the position shown in Fig. 1 until the press reaches a safe closed position. These blocks are rigid with shaft 34, which has an arm 35 connected by rod 36 with one of the press parts. As here shown the rod 36 passes through a slotted bracket 31 on toggle M. The rod carries collars 31a and 31b and is normally biased to hold the blocks in the position of Fig. 1 by a spring 38.

With the press in the open position of Fig. 1, the operator depresses manuals 38 and 3| to the position of Fig. 2. Depression of one manual takes up the lost motion provided by the air gap 39. Operation of both manuals coincidentally is necessary to move the link portion Zla to the position of Fig. 2, thus rotating lever 20 in a clockwise direction and moving valve core 18d to the position of Fig. 2, cutting out the exhaust port 18a and establishing fluid supply to motor l5 through conduit ll, valve casing l3 and conduit l9. During this operation the latches 22 have moved idly in the slots 26 and if either of the manuals now is released, the catches will engage the arms 25 and the upward movement of the manuals and whifiietree will carry the link portion Zla with it, returning the valve core Hid to the position of Fig. 1. Upon the press reaching safe closed position, the blocks 33 are moved to the position of Fig. 3, whereupon the manuals may be further depressed as shown, moving lever 23 somewhat farther in a clockwise direction but without any further eifect upon press control. During this additional movement of the manuals, link 2 la carries the latches 22 between the fixed members 2'! so that the latches are moved inwardly as shown in Fig. 3, withdrawing them from the slots 26 in arms 25. Upon release of the manuals from the position of Fig. 3, the link portion 2lb will return upwardly with the manuals, but the link portion 2Ia, lever 21! and the valve core IBd will remain in the position of Fig. 3 and the press will remain closed. The manuals may then be released, whereupon they will return to the position of Fig. 4 carrying with them the whifiietree and link portion 2H9. To release the press the arm 200 of lever 29 is moved in a counterclockwise direction returning the parts to the position of Fig. 1, thus exhausting motor I5 and permitting the press to open. This return of the parts to the position of Fig. 1 again engages the latches 22 in the slots 25, ready for the next operation.

What I claim is:

1. In a pressing machine having coacting relatively movable pressing members and power actuated operating mechanism therefor, a control. member for supplying power to said mechanism adapted to remain in any position in which it is placed, manual means for actuating said control member and having first and second stages of operation, said manual means in the first stage of operation thereof having an operarive connection with said control member requiring coincidental movement of two hands of an operator for actuation thereof sufficient to move said control member to power-supply position, means for preventing second stage operation or said manual means until said pressing members reach safe-closed position, means for returning said manual means to unoperated position during first stage operation of said manual means, releasable means connecting said manual means and said control member, and means for releasing said connecting means by second stage operation of said manual means, said control member being movable to power cut-oif position to permit opening of said pressing members.

2. In a pressing machine having coacting rela-- tively movable pressing members and power actuated operating mechanism therefor, a control member for supplying power to said mecha-:

nism adapted to remain in any position in which it is placed, manual means for actuating said control member including two manuals spaced to require two hands of an operator for coincidental operation thereof, said manual means having first and second stages of operation, an operative connection between said manuals and said control member requiring first stage actuation of both manuals to move said control member to power supply position, means for preventing second stage operation of said manual means until said pressing members reach safeclosed position, means for returning said manual means to unoperated position during first stage operation of said manuals, an equalizer bar connected between said manuals, means for latching said equalizer bar to said control member, and means for unlatching said latching means by second stage operation of said manual means, said control member being movable to power cutoff position to permit opening of said pressing members.

3. In a pressing machine having coacting relative- 1y movable pressing members and power actuated operating mechanism therefor, a control member for said mechanism adapted to remain either in power supply or power cut-off position, a pair of manuals spaced to require a hand of the operator on each of them for their coincidental operation, stop means preventing movement of said manuals beyond an intermediate position, means responsive to movement of said pressing members to safe-closed position for removing said stop means, an equalizer bar connecting said manuals, means for returning said equalizer bar to unoperated position, releasable means connecting said bar to said control member and arranged to move said control member to power supply position upon coincidental operation of said manuals to said intermediate position, and means for releasing said connecting means upon operation of said manuals beyond said intermediate position, said oontrol member being movable to power cut-off position to permit opening of said pressing members.

ELBERT L. HYDE. 

